Optimisation
Most companies involved in engineering design are under ever increasing pressure to minimise cost and weight of their products and to deliver these designs in ever reducing timescales. To help our clients deliver these objectives Vectayn incorporates advanced optimisation techniques into our working methodology to allow these goals to be met.
For linear analysis, Vectayn use the capabilities of the Hyperworks suite to help deliver an optimised design, this gives us the ability to carry out the following types of optimisation:
Topology
This is a mathematical technique that optimises the material distribution for a structure within a given package space. This has the effect of removing material that is not contributing to the structural performance of the component to leave the optimised structure
Free Size
A mathematical technique that produces an optimised thickness distribution for each individual element in a 2D structure. This technique can be used to identify where material can be removed from 2D (shell element) structures, as well as showing where material thickening or addition of ribs would be beneficial for the structural performance.
Size
An automated method to modify the structural parameters of a model to find an optimal design. This method would generally be used to ‘fine tune’ a design and could consider a number of parameters including thickness, beam properties, material properties, etc.
Shape
This is an automated method to modify the shape of a component based on predefined shape variables. This allows the design of a component to be ‘fine-tuned’ within set limits to give an optimised design for the load cases considered.
Free Shape: A strategy similar to the shape optimisation but without the predefined limits on the changes of shape permitted.
Topography: An advanced form of shape optimisation in which a design region for a given part is defined and a pattern of shape variable reinforcements within that region is generated. This is most commonly used to define optimised swage patterns to stiffen 2D structures.
Composite Shuffle: This is automated method to determine the optimum laminate stack sequence. This is a powerful tool to help design composite structures with optimised ply thickness, direction and order.
For non-linear large displacement analysis, typically crash and impact events, Vectayn applies the capabilities of either LS-Opt or Hyperstudy to help understand and optimise these types of structure. Some of the capabilities and types of analysis this allows us to carry out are outlined below:
Design Exploration
The production of ‘Meta Models’, produced by running a series of analyses to evaluate all desired variables, allow ‘response surfaces’ to be produced. This allows an understanding of how each design variable effects the performance of the system by interpolating between the data points.
Sensitivity Studies
The Meta Model allows the sensitivity of a design objective to be assessed against each design variable. This then allows the design variables to be ranked in terms of importance to changing the system objective.
Optimisation: By incorporating an iterative process and setting allowable parameters to the design, the software will optimise the design to meet the defined objective. The parameters applied to the design could include:
- Part thickness changes
- Material property changes
- Geometric changes
- Loading variations
Robustness Studies: Once a design has been produced a robustness study can be carried out to evaluate how sensitive the design is to a series of design parameters.
The benefits of an analysis led optimisation programme include
Reduced Cost – Optimisation can be used to reduce cost in a number of ways, these include:
- By generating component designs optimised to give minimum mass, the cost of the part can be reduced.
- By maximising the stiffness of components, the number of attachments between parts can be reduced resulting in an overall assembly cost reduction.
Improved performance – By intelligent use of the optimisation tools the structural performance of individual components and complete assemblies can be improved.
Reduced Development Time – The optimisation process can identify the best design for a part/assembly at an early stage of the design process hence reducing the design timescale compared to a more traditional approach. This has the added benefit of reducing the design and development cost.